Shock shielding structure and method

ABSTRACT

A shock shielding structure and method for shielding against shock by the use of inflated envelopes wherein said shielding is capable of functioning at peak reflected shocks of over 2,000 pounds per square inch to reduce the peak transmitted force by 70-90 percent or more. Still further, the shielding invention herein comprises a sheltering method and structure for use against the dangers incident to war and, more specifically, relates to a method or structure for use in shielding persons or equipment against the effects of nuclear explosion, and also toxic or corrosive gases and bacteria.

SEARCH ROOM I United States Patent [1 1 3,660,951 Cadwell 1 May 9, 1972 [541 SHOCK SHIELDING STRUCTURE AND 2,838,341 6/1958 Watson ..52 2 METHOD 3,044,515 7/1962 3,086,753 4/1963 [72] lnventor: Sidney M. Cadwell, 436 Washington 3 227 1 9 1 19 Road, Grosse Pointe, Mich. 48236 3,256,440 6/1966 [22] Filed: June 24,1968 3,104,441 9/1963 Smith ..161/92 [21] Appl. No.: 739,351 Primary Examiner-Reinaldo P. Machado s Attorney-Harness, Dickey & Pierce Related US. Application Data [63] Continuation-impart of Ser. No. 425,497, Jan. 14, [57] ABSTRACT 1965, abandoned. A shock shielding structure and method for shielding against shock by the use of inflated envelopes wherein said shielding is [52] US. Cl ..52/2, 109/15 capable of functioning at peak reflected shocks of over 2,000 [51] Int. Cl ..E04b 1/345 p n s per square inch to reduce the peak transmitted force 58 Field of Search ..52/2; 109 15; 49/460,'9, 34, y 70*90 percent or more Still further. the shielding in n- 49 3 35 tion herein comprises a sheltering method and structure for use against the dangers incident to war and, more specifically, 56] References Cited relates to a method or structure for use in shielding persons or equipment against the effects of nuclear explosion, and also ED AT TS toxic or corrosive gases and bacteria.

2,819,724 1/1958 Barker ..52/2

17 Claims, 7 Drawing Figures PATENTEDMAY 9|972 3.660851 sum 1 OF 3 INVENTOR. Sidney M [ad/42 x71 :1, WV da ing f7 TTOR/IE 5.

PATENTEDMAY 9 |972 SHEET 2 OF 3 SHOCK SHIELDING STRUCTURE AND METHOD CROSS REFERENCE TO RELATED APPLICATION This application is a continuation-in-part of the copending application of Sidney M. Cadwell filed Jan. l4, 1965, Ser. No. 425,497, entitled "Sl-lELTER and now abandoned.

BACKGROUND OF THE INVENTION With the advent of modern warfare and the use of atomic, chemical and biological weapons, it becomes necessary to protect our retaliatory personnel, equipment and structures from the effects of these weapons. This protection is required if we are to be capable of delivering a retaliatory offensive in the event these weapons are used in committing a nation to war. While certain devices and structures are presently available for this use, they do not provide the degree of protection required as compared to the weight and expense involved. In certain cases, the prior structures and devices are too cumbersome to afford any degree of mobility to the user.

in providing protection of equipment against the blast effects of an atomic explosion, it has been discovered that a structure or structures may be pressurized in the form of inflated envelopes to a degree such that the shock wave force of the explosion is not transmitted through the structure and into the structural interior thereof. Further the discovery has been made that the peak shock wave or peak transmitted force normally of short duration following an explosion, which peak shock wave causes the most substantial damage after an explosion, can be substantially mitigated in its effect because the shielding method and structures of the type disclosed herein result in the peak transmitted force being reduced in magnitude and spread out over a longer time duration relative to the effect of the transmitted force which is experienced or felt within said structures. Hence, the overall result is that the transmitted force is reduced and spread out over a longer time period to thereby avoid the substantial damage which occurs when a peak force strikes a structure instantaneously.

ln protecting personnel, in addition to equipment, it has been found that by placing one or more pressurized envelopes between the blast and the personnel, wherein the envelope(s) has been pressurized the shock wave will be reflected and substantially reduced to before entering the interior of the structure. In a specific example, it has been discovered that by using a fabric reinforced inflated rubber envelope, the shock wave produced by an explosion would not be transmitted to the interior thereof and that measuring equipment placed within the structure did not register any appreciable indication of the presence of the shock wave. Thus, personnel and equipment placed within the envelope would be protected against explosion shock waves. In view of the sealed envelope and the thickness thereof, the personnel would also be protected from toxic or corrosive gases and bacteria.

More specifically and merely as an example, a missile of the type which is normally mounted in a vertical position and ready to tire, might be enclosed in a fabric reinforced rubber envelope which has been suitably sealed and supported in the upright position. The interior of the envelope is inflated to a pressure which is greater than the total shock wave pressure which could be anticipated from an atomic explosion at the assumed distance that the envelope is placed from the point of explosion. it has been found that the missile would be protected against the forces of the shock wave, the fire wave, wind and certain of the radiation effects of the blast which would be encountered at a missile site. In determining the pressure to which the interior of the envelope is to be inflated, it is necessary that a calculation be made as to the total blast pressure or total shock wave pressure which could be expected at that point.

These calculations are normally made by estimating a probable ground zero area in the vicinity of the missile site; and, through the known relationship that the shock wave pressure decreases inversely as the cube of twice the distance from the explosion, the pressure at the missile site may be calculated.

The discovery has also been made that the inflated envelope or envelopes broadly described herein may be divided into two specific categories termed a soft envelope" and a "hard envelope."

The pressure of inflation within the envelope on a broad basis, regardless of the type envelope, should not be lower than about 2%pounds per square inch (pressures referred to herein represent the pressure above atmospheric pressure, conventionally described as pounds per square inch gauge or abbreviated as psi) and preferably not lower than 5 psi; and, the upper limit normally will not exceed 3,000 psi and more specifically the upper pressure will generally be of a magnitude of about 2,000 psi or less.

The soft envelope inflation pressure, within the above broad ranges, should generally be within the range of about 2%up to about psi; and, preferably from about 5 up to about 100 psi.

The hard envelope inflation pressure, within the above broad ranges, should generally be within the range of about 100 to about 3,000 psi; and, preferably from about 100 to about 2,000 psi. It should be understood that the intermediate pressure of 100 psi stated above as the point of division between the hard and soft envelopes is somewhat relative, and perhaps it could be more aptly stated that the point of division may actually be of a greater or lesser magnitude so long as the concept is met that the soft envelope is inflated to a pressure considerably lesser magnitude than the hard envelope.

The inventive concept underlying the above described hard and soft envelopes is based on the discovery that a soft envelope generally attenuates or protects best against the peak shock wave resulting from an explosion, whereas a hard envelope generally attenuates or protects best against the vibrations or reduced shock waves following an explosion. This concept is discussed more fully hereinafter in relation to certain structural embodiments of the invention.

In carrying out the principles of the present invention, it is contemplated that the simplest fonn of the structure will be fabricated from a rubber exterior or outer covering witha single or plurality of layers or plies of weftless or woven fabric. The fabric may be constructed of any of the natural fabrics, such as cotton, silk, wool, or any of the synthetic fabrics, such as nylon, rayon, dacron. It is further contemplated that the plies could be constructed of such materials as steel or glass weftless or woven fabric. in cases where the pressure within the structure or structures is relatively low, little or no reinforcement will be necessary and the structure may be wholly constructed of a thick wall of carbon black reinforced rubber or other material. It is contemplated that the thickness of the rubber in this latter case will be of the order of one-fourth to 1 inch in thickness, depending on the internal pressure of the envelope. If greater thicknesses are utilized, a certain amount of attenuation of the shock wave will be achieved within the wall itself.

While the invention will be described as being primarily composed of rubber and fabric, it is to be understood that any polymeric or plastic material that is solid and, importantly, is somewhat flexible at ordinary temperatures may be used. These materials include all synthetic rubbers and all plastics which exhibit the above described characteristics. Other considerations in the exterior covering are the ability to withstand heat and the radiation effects of the atomic blast along with the characteristics of being impervious to chemical and bacteriological materials which may be used. Similarly, the exterior covering may be chosen for its capability of inherently attenuating shock waves; and, in this regard, it is to be noted that rubber has an inherent characteristic of attenuation of shock waves, the attenuation being proportional to the thickness of the rubber employed.

In carrying out the principles of one embodiment, the invention in the protection of personnel in addition to equipment, it is contemplated that the structure will be built up of a double wall configuration, the wall construction being of the type described above, with the portion between the two walls pressurized. Through this double wall construction it is only neces sary that the space between the two walls be sufficiently pressurized and the interior of the structure may be maintained at atmospheric pressure. In this way, it is not necessary that the personnel contained in the shelter wear pressurized suits or other encumbering apparatus.

As an illustrative example, it is contemplated that the wall will be compartmentized or constructed of a plurality of air ockets, with each compartment pressurized to the calculated pressure. Thus, the possibility that the pressurizing fluid would escape from the whole envelope if the envelope were punctured is precluded. If the fluid were lost from the whole envelope, the personnel contained therein would be vulnerable to subsequent blast and radiation effects.

In carrying out certain other principles of the present invention, it is contemplated that part or all of the surfaces of the reinforced rubber may be covered with metal plates or the like or a portion of the surface structure may be metal with other portions of rubber construction. As an example, in the case of a submarine, it is contemplated that a double metal wall would be built up around the submarine with a pressurized double wall construction disposed between the two separated metal walls. The inner metal may be the outer hull of the submarine or vessel. Thus, the peak pressures which are impressed on the exterior of a submarine, due to the explosion of depth charges or the like, will be reduced to the point where the force will not be transmitted from the exterior metal wall to the interior metal wall.

In this way, the waterproof inner metal covering of the submarine will not be penetrated or buckled due to the explosion, thus precluding the entry of water to the interior of the submarine. Similarly, certain portions, or all areas, of surface ships may be enclosed in a structure of the type described above; that is, the double wall construction, to protect personnel or equipment which may be contained therein. Thus, in the case of a landing ship, the personnel which are contained within the interior of the landing ship may be protected from blasts by providing a protective covering of the type described above.

In choosing the fluid with which the structure is to be pressurized, it is contemplated that air or nitrogen are preferable gases to be used, but any permanent type of gas may be chosen. In choosing the gas for inflating the structure, due consideration must be had to the diffusibility, combustibility and explosibility of the gas. It is preferable to have a gas which is inert in its explosive or combustive character and diffuses only slowly, and it is further desired that the gas be electrically insulating.

Accordingly, it is one object of the present invention to provide an improved shelter against the effects of atomic explosion.

It is another object of the present invention to provide an improved shelter for the protection of personnel and equip ment against the effects of an atomic explosion and/or the effects of chemical and biological warfare.

It is another object of the present invention to provide a structure which is capable of eliminating the shock effect produced by a pressure wave created by an atomic explosion.

It is still another object of the present invention to provide an improved structure for protecting vessels against the effect of explosions.

It is still another object of the present invention to provide a structure which is capable of protecting submersible vehicles, such as submarines, diving bells, or other submerged objects, against the effects of explosions under the sea.

It is still a further object of the present invention to provide an improved shelter against the effects of atomic explosion which is easy to use, simple in its construction, lightweight and highly mobile.

It is a further object of the present invention to provide an improved shelter which is capable of protecting equipment and personnel against fire and blast effect and alpha and beta radiation.

It is still a further object of the present invention to provide an improved structure which is capable of being inhabited by humans and protects them against the effects of an atomic explosion.

It is still a further object of the present invention to provide an improved shelter which is sturdy in use and inexpensive to construct.

The manner of accomplishing the foregoing objects and other objects and features of this invention will become apparent from the following description of embodiments of the invention when read with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a representative illustration in cross section of a missile silo wherein certain principles of the present invention are being utilized;

FIG. 2 is a cross-sectional view taken along lines 3-3 of FIG. 1, illustrating one preferred construction of the walls of the structures of FIGS. 1 and 3;

FIG. 3 is a cross-sectional view of a shelter for personnel and equipment utilizing certain other principles of the present invention;

FIG. 4 is an illustration in cross section of another embodiment of a structure for use in protecting personnel and equipment;

FIG. 5 is a cross-sectional view of the door structure to be utilized in the shelter illustrated in FIG. 4;

FIG. 6 is a cross-sectional view of the door structure of FIG. 5 illustrating the door in position on the shelter of FIG. 4;

FIG. 7 is a cross-sectional view partially illustrating a construction embodying the principles of the invention to be utilized in protecting submersible and surface vessels in addition to land vehicles; and

FIG. 8 is a illustration in cross-section of another structural embodiment wherein a hard envelope is utilized in combination with an overlying soft envelope.

SUMMARY OF THE INVENTION From a structural aspect, briefly stated, the present invention comprises a structure for protecting personnel and/or equipment from the effects of an explosion having a shock wave pressure comprising: a first high strength, relatively rigid, material liner means for partially carrying out said protecting and being formed generally of a protective shape and having its general extremities sealed to a surface, a second flexible resilient liner means for partially carrying out said protecting and being formed generally of a protective shape having at least a portion thereof disposed spaced from said first liner means and said second liner means having its general extremities sealed to a surface, and means pressurizing the space between said first and second liner means to a pressure at least as great as the shock wave pressure.

From a method aspect, briefly stated, the present invention comprises a method of using a structure to protect against the effects of an explosion having a shock wave pressure, said structure being comprised of: a first high strength, relatively rigid, material liner means for partially carrying out said protecting and being formed generally of a protective shape, a second flexible resilient liner means for partially carrying out said protecting and being formed generally of a protective shape having at least a portion thereof disposed spaced from said first liner means, means pressurizing the space between said first and second liner means to a pressure between about 5 and about 3,000 pounds per square inch, to thereby form a pressurized envelope, said method comprising the steps of: (A) assembling said structure in a desired orientation and environment, and (B) using said structure to protect personnel and/or equipment from said effects of explosion.

It should be understood that the terminology used herein is meant to be construed broadly, and for example, by the terminology liner or liner means it is meant a liner or wall structure which may be made of numerous satisfactory materials and which may be of numerous shapes.

DESCRIPTION OF PREFERRED EMBODIMENTS Referring now to FIG. I, there is illustrated a representation of a silo containing a missile 12 therein of the type which is either adapted to be fired while stillwithin the silo, or may be raised to a point above the level of the earth for firing. The silo 10 is constructed of a concrete casing 14 which surrounds the missile 12 having a pair of access tunnels 16 and 18 emanating therefrom. The lower portion of the silo 10 is provided with a pad assembly 20 which supports the missile l2 and may be used to raise the missile 12 above the ground into firing position. lnterposed between the walls 14 of the silo l0 and the missile 12 is a pressurized envelope 22 of the type utilizing principles of the present invention.

ln constructing the silo 10, a portion of the earth 24 is dug out and suitable forms are provided to fabricate the walls thereof. The upper portion of the silo 10 is provided with a door mechanism 26 having a pair of doors 28, 30 which may be opened just prior to the firing of the missile 12. The access tunnels l6 and 18 are integrally formed with the walls of the silo and provide easy access to the missile for testing and inspection purposes. The fioor of the silo 10 is provided with the pad assembly 20 which includes a raising and lowering mechanism, partially illustrated as structural elements 32, 34 and 36, and a source of power (not shown) to provide power to the structural elements 32, 34 and 36, thereby raising the missile into the firing position. Intermediate the ends of the silo, a second floor 38 is provided for a purpose to be hereinafter explained.

The shelter assembly 22 generally comprises a reinforced rubber envelope 40, which is of I a construction to be hereinafter explained, and a support pad 42 contained therein which is adapted to resiliently support the missile 12 within the envelope 40. The envelope 40 is constructed of a generally circular side wall section 42 and a bottom 44 integrally fonned therewith. The top of the envelope 40 is provided with a pair of overlapping ends 46, 48 which are suitably sealed to each other as by a sealant 50. The method of sealing the upper portion of the envelope 40 is not critical to the invention, but it is contemplated that the upper surface of overlapping portion 46 may be suitably fastened against the cover portion 52 of the intermediate cover 38 with the upper surface of the other overlapping portion 48 bearing against the lower surface of the overlapping portion 46 with the sealant 50 maintaining the two portions 46, 48 in position.

The interior 54 of the envelope 40 is suitably pressurized through a pressure valve 56 which may be of any known construction. Thus, as the interior 54 is pressurized to the desired pressure, the overlapping portion 48 is forced outwardly into sealing engagement with overlapping portion 46. The sealant 50 may be of any compressible, tacky substance which will adhere to member 46 under pressure and may be released on a relief of the pressure in envelope 40.

The envelope 40 is suitably held in place by fastener brackets 60 which may be of any construction or of the configuration illustrated in FIG. 1, and which are embedded into the side walls 14 of the silo 10. A suitable pressure gauge 62 is also provided which is adapted to read the interior pressure of the envelope 40 and the exterior pressure or atmospheric pressure in a normal situation, or shock wave pressure in a situation where an explosion has occurred. Thus, the operating personnel of the missile site may be provided with information as to the differential pressure between the interior and exterior of the envelope 40.

In operation, and when it has been determined that an explosion has occurred, the operating personnel watch the indication of the pressure gauge 62 for an indication that the pressure in the area exterior to the envelope 40 has dropped to atmospheric pressure. This indicator preferably will be mounted at a remote position from the gauge 62. In this regard, it is to be noted that the initial shock wave pressure caused by the blast will be registered and a second shock wave pressure will be registered sometime later, the second pressure being caused by the rush of air and debris into the vacuum created by the explosion. It is not until after the second pressure indication that the missile will be readied for operation; When it is decided to fire the missile, the door 52 is operated along with doors 26 and 28, thus opening the way to the exterior of the silo 10. When door 52 is open, the upper overlapped portion 46 will be carried therewith, and any suitable mechanism will be provided to open or extend lower overlappingportion 48. In this regard, suitable conventional interlocking mechanism between overlapping portions 46' and 48 may be provided. With the opening of the overlapping portions 46 and 48, the pressure 'within the envelope 40 will be reduced to atmospheric pressure and the missile will be ready for operation. If the missile is to be raised from the silo, a suitable source of power must be provided to shear the clamping members 60 from the wall 14 of the silo 10 in order to free the missile 12 and its envelope 40 from the silo. In the alternative, the pad 20 may be made smaller than the bottom 44 and the envelope 40 will be inverted as the missile 12 is raised.

FIG. 2 representatively illustrates one preferred construction of the wall of the'envelope 40. As is seen from FIG. 2, the wall is constructed of an exterior layer 70 of rubber or other material, as described above, with a plurality of layers or plies of reinforcing fabric 72 provided on the interior thereof. The interior of the wall is provided with an inner sealing liner 74 which prevents any appreciable amount of the pressurized fluid from entering the plies 72 and separating them or separating the plies 72 from the exterior layer 70. The plies 72 are built up of a plurality of layers of fabric such as would be normally found in a tire construction. As stated above, these plies may consist of weftless fabric or woven fabric formed of any natural or synthetic fibers as will as steel or glass. The plies are utilized primarily for structural rigidity and strength and are suitably chosen forthese characteristics. v

Referring now to FIG. 3, there is illustrated an alternate embodiment of the present invention which may be primarily utilized for protecting equipment which is operated by personnel and the personnel which may be contained therein. The structure 78 is representatively illustrated as being constructed of an open ended barrel-shaped member 80 with an upper end member 82 and a lower end member 84 closing off the ends of the barrel member 80. The personnel and equipment are enclosed within the space provided between members 82 and 84. The interior of barrel member 80 is lined with a tubular steel liner 8510 support member 80 and a top disc 87 and bottom disc 89 are provided for additional strength. It is to be understood that member 80 may additionally include suitable structural truss members, not shown, for structural rigidity.

The walls of members 80, 82 and 84 are constructed of a double wall member 86 having an outer wall 88 and an inner wall 90 joined at either end by a layer of rubber 92, 94 to seal the ends thereof. As a certain amount of-pressure may enter at the point where the top 82 is joined to barrel member 80 and the bottom 84 to member 80, a pair of generally circular pressurized fillets 91, 93 have been provided. It is to be noted that the interior of the fillets 91, 93 are hollow and pressurized as in the case of members 80, 82 and 84 to reflect any shock wave encountered at the juncture of members 82, 80 and 80, 84. At least one and, in many cases, a plurality of intermediate rib members 96 are provided intermediate the ends of the wall member 86. Thus, the barrel-strapped wall member 86 is suitably compartmentized by the plurality of intermediate members 96, which provide air pockets 98 and 100 within the wall member 86. As was described above, this compartmentizing provides additional safety for the interior of the barrel member 86 to provide against the contingency of foreign objects puncturing one of the compartments 98 or 100, and precluding the loss of the entire pressurized area between the outer wall 88 and inner wall 90. It is to be noted that the wall 86 is provided with additional members (not shown) which extend longitudinally of the barrel-shaped member 80, thereby co'mpartmentalizing the structure in the transverse direction. The top and bottom members 82 and 84 are similarly formed, thus providing a cellular type structure for the whole construction.

The top and bottom members are suitably attached to the barrel member 80 by any method which will provide rigidity and strength to the structure. It is to be noted that access to the interior of the structure must be provided and this may be done through any suitable access opening (not shown) in the top 82 or in the barrel member 80. The wall construction 88 and 90 and the wall construction of the top and bottom members 82 and 84 are formed similar to that shown in FIG. 2, and the outer wall 88 is turned back to back with the inner wall 90 and the upper and bottom members are similarly constructed. The interior of the member 80 is provided with the equipment to be protected along with an air-conditioning and oxygen unit 102 to provide oxygen and comfort to the personnel and additionally to lower the temperature in the structure due to the heat dissipated by the equipment contained therein. It is contemplated that the site at which the structure of FIG. 3 is used may be sufficiently spaced from the anticipated point of explosion of the atomic weapon such that the top 82 may be omitted, thereby still providing protection against blast effects for the equipment and personnel contained within the structure 78.

As an alternative use of the construction illustrated in FIG. 3, it is further contemplated that the member 80 may be used or a pair of rectangular members of the construction illustrated in FIG. 3 be placed at a point spaced from the point of explosion and personnel could position themselves between the two rectangular members. In this use, the rectangular members will be positioned with the flat side thereof facing the point of explosion thereby protecting the personnel from the direct blast. The back portion or other wall will be placed behind the personnel further spaced from the point of explosion to protect the personnel from the counterblast which will be produced by air and debris rushing into the vacuum created by the initial blast. In this way, an extremely simplified and easily transportable structure is provided for the protection of personnel and equipment. It is anticipated that a structure of this type will be utilized in an area where the pressure would not be too great as to endanger the personnel.

Referring now to FIGS. 4, 5 and 6, there is illustrated another modification of the structure of FIG. 3, incorporating the principles of the present invention, and adapted to be utilized in protecting personnel and equipment. In FIG. 4 there is shown a hemispherical dome-type shelter 110 which is generally constructed of an inner steel or similar metal shell 112 and an outer shell 114, spaced therefrom and constructed of rubber or other suitable material. It is to be noted that the outer shell 114 may be formed solely of a rubber layer or may be formed of a construction similar to that illustrated in FIG. 2. The two shells, 112 and 114, are suitably anchored at the lower edges thereof by embedding the edges in concrete or attaching them to a series of concrete posts 116 by means of a plurality of fasteners 118. The space between the inner shell and outer shell 114 is pressurized to a pressure which is sufficient to reflect the explosive shock wave which may be anticipated, as described above. Moreover, the pressure between shells 112 and 114 may be such as to form a hard envelope protective shelter or a soft envelope protective shelter, as discussed hereinabove, or still further the structure may be such as to form a soft envelope over a hard envelope type structure as shown in FIG. 8. The floor of the shelter is protected from any bomb tremors or other shock waves received generally upwardly from the ground by means of a pressurized floor assembly 120 which may be compartmentalized, as described in conjunction with FIG. 3, and is pressurized to a pressure which is of the same order of magnitude as the pressure between shells 112 and 114.

The floor assembly may be fonned of a plurality of generally concentric circular compartments having a plurality of cavities 122 formed therein which are suitably attached to each other in any well known manner, as for example by, attaching in the molding process. Also, the floor may be formed of a plurality of small, closely spaced cells, as would be the case in the cellular structure of greatly magnified foam or other closed cell material. However, to facilitate the pressurizing of the floor assembly, it is contemplated that the concentric circular structure would be preferable. The interior of the structure may be provided with visual access to the exterior of the dome 110 by means of a periscope 124 and suitable airconditioning equipment 126 or other convenient facilities, such as a lavatory and washing facilities.

Entrance to the dome structure of FIG. 4 may be provided with a door assembly 129, the details of which are illustrated in FIGS. 5 and 6. A door 128 is provided in the dome structure and is of a similar steel construction as the liner 112 to provide the same structural rigidity as the dome structure. The exterior of the door 128 is covered with a pressurized cover assembly of a type similar to that illustrated in HG. 3, that is, the covering assembly comprises an outer wall 130 and an inner wall 132 joined by a plurality of webs 134. Similarly, a plurality of longitudinally extending webs (not shown) may be provided to further compartmentalize the interior structure between the walls 130 and 132. As in the previous cases, the cavities of the shells provided by walls 130, 132 and 134 would be pressurized by pressure which was of the same magnitude as the pressure between shells 112 and 114.

FIG. 6 illustrates the door structure 129 in the closed position and it is to be noted that the upper portion of the door overlaps the lower portion of the outer shell 114 which converges with shell 112 to provide a sharp angle between the inner shell 112 and outer shell 114. While the pressure between shell 112 and 114 would be the same at this area as in other areas of the dome structure, the portion of the dome structure where the two shells 112, 114 meet, would have to be protected by a pressurized area; thus an overlapping is provided. Similarly, at the bottom, a close fit between the ground and the door 129 is provided to preclude shock wave pressure from entering the interior of the dome at a point adjacent the ground level.

FIG. 7 illustrates a further embodiment of the present invention which is particularly adapted to be utilized on submerged vehicles such as submarines, diving bells, submerged equipment and other like objects. Also the construction illustrating FIG. 7 may be utilized on the hull of a surface ship or other vehicles to provide protection from torpedo or bomb explosions which may occur adjacent a ship.

The modification is only shown partially, and it is to be understood that the structure illustrated would be provided around the complete exterior of the ship or vessel of the type described. The structure is applied to an outer hull of the ship and a second blister wall 142 has been applied thereto spaced from the hull 140. The space between the two metal walls 140, 142 is filled with a cellular structure 144 fabricated of a generally flexible material. The cellular structure 144 may be composed solely of a layer of rubber or may be formed of the wall construction illustrated in FIG. 2. The structure 144 generally comprises a pair of walls 146, 148 which are joined at their ends by webs 150 to suitably seal the sides of the cell. The interior of the cell is pressurized to a pressure which is greater than the expectant shock wave pressure from an explosion which may occur nearby. Thus, the peak force of the explosion hitting the blister wall 142 will be substantially reduced by the walls 146, 148 and the internally pressurized volume. With this type of construction applied to the exterior or surface of a ship, torpedo or bomb explosions which may occur in the vicinity of a surface vehicle or depth charge explosions in the case of a submarine, will be reflected and the hull 140 will remain intact, thereby precluding the flooding of the interior of the vessel. It is to be understood that this type of construction may also be used on land vehicles, such as personnel carriers, trucks or the like, to provide protection for the personnel or cargo contained therein.

FIG. 8 illustrates a further embodiment of the invention, similar to FIG. 4, but wherein the shelter structure is comprised of a first pressurized hard envelope formed by the shells 112 and 114, and a second pressurized soft envelope formed by the shells 115a and 1l5b. It should be noted that the soft rubber envelope so formed surrounds or overlays the hard envelope for the reason that the soft envelope attenuates or protects best against the peak shock pressure, whereas the inner hard envelope attenuates or protects best against vibrations which generally may be considered to follow the peak shock pressure. Of course the FIG. 8 structure, and for this matter the FIG. 4 structure also, are very specific illustrative embodiments; and, it should be understood that numerous variations therein, such as changes in geometric design, materials of construction, size, etc., may be made without departing from the concept and scope of this invention.

While it will be apparent that the embodiments of the invention herein disclosed are well calculated to fulfill the objects of the invention, it will be appreciated that the invention is susceptible to modification, variation and change without departing from the proper scope or fair meaning of the subjoined claims.

What is claimed is:

1. A shelter for protecting personnel and/or equipment from the effects of an explosion having a shock wave pressure comprising:

a metal dome-like inner liner formed generally hemispherical in shape and having its edges sealed to a surface,

a flexible dome-like outer liner formed generally hemispherical in shape having at least a portion thereof disposed spaced from said metal inner liner and having its edges sealed to the surface, and

means pressurizing the space between said inner and outer liner to a pressure at least as great as the shock wave pressure.

2. The shelter of claim 1 further including a door for gaining access to the interior of the shelter having an interior metal liner and an outer structure formed of an outer flexible wall,

an inner flexible wall spaced from said outer wall and disposed adjacent said interior metal liner,

flexible web means interconnecting said inner and outer flexible walls forming cavities for compartmentalizing said space, and

compressible fluid means pressurizing said cavities to a pressure at least as great as said shock wave pressure.

3. A structure, for protecting personnel and/or equipment from the effects of explosion having a shock wave pressure, comprising:

a metal inner liner means for partially carrying out said protecting and being formed generally of a protective shape and having its edges sealed to a surface,

a flexible outer liner means for partially carrying out said protecting and being formed generally of a protective shape having at least a portion thereof disposed spaced from said metal inner liner means and said outer liner means having its edges sealed to a surface, and

means pressurizing the space between said inner and outer liner means to a pressure at least as great as the shock wave pressure.

4. A shelter for protecting personnel and/or equipment from the effects of an explosion having a shock wave pressure comprising:

a metal dome-like inner liner formed generally hemispherical in shape and having its edges sealed to a surface,

a flexible dome-like outer liner formed generally hemispherical in shape having at least a portion thereof disposed spaced from said metal inner liner and having its edges sealed to the surface, and

means pressurizing the space between said inner and outer liner to a pressure between about 5 and about 3,000 pounds per square inch.

5. Astructure as in claim 3 wherein said means pressurizing the space between said inner and outer liner means is pressurized to a pressure between about 5 and about 3,000 pounds per square inch.

6. A structure for protecting personnel and/or equipment from the effects of an explosion having a shock wave pressure comprising:

a first high strength, relatively rigid, material liner means for partially carrying out said protecting and being formed generally of a protective shape and having its general extremities sealed to a surface,

a second flexible resilient liner means for partially carrying out said protecting and being formed generally of a protective shape having at least a portion thereof disposed spaced from said first liner means and said second liner means having its general extremities sealed to a surface, and 7 means pressurizing the space between said first and second liner means to a pressure at least as great as the shock wave pressure.

7. A structure as in claim 6 wherein said means pressurizing the space between said first and second liner means is pressurized to a pressure between about 5 and about 3,000 pounds per square inch.

8. The structure of claim 1 further including a door for gaining access to the interior of the shelter having an interior metal liner and an outer structure formed of an outer flexible wall,

an inner flexible wall spaced from said outer wall and disposed adjacent said interior metal liner,

flexible web means interconnecting said inner and outer flexible walls forming cavities for compartmentalizing said space, and

compressible fluid means pressurizing said cavities to a pressure at least as great as said shock wave pressure.

9. A method of using a structure to protect against the effects of a nuclear explosion having a shock wave pressure, said structure being comprised of:

a metal dome-like inner liner formed generally hemispherical in shape and having its edges sealed to a surface,

a flexible dome-like outer liner formed generally hemispherical in shape having at least a portion thereof disposed spaced from said metal inner liner and havings its edges sealed to the surface, and

means pressurizing the space between said inner and outer liner to a pressure at least as great as the shock wave pressure,

said method comprising the steps of:

A. assemblying said structure in a desired orientation and environment, and

B. using said structure to protect personnel and/or equipment from said effects of explosion.

10. A method of using a structure to protect against the effects of a nuclear explosion having a shock wave pressure, said structure being comprised of:

a first high strength, relatively rigid, material liner means for partially carrying out said protecting and being formed generally of a protective shape and having its general extremities sealed to a surface,

a second flexible resilient liner means for partially carrying out said protecting and being formed generally of a protective shape having at least a portion thereof disposed spaced from said first liner means and said second liner means having its general extremities sealed to a surface, and

means pressurizing the space between said first and second liner means to a pressure at least as great as the shock wave pressure,

said method comprising the steps of:

A. assembling said structure in a desired orientation and environment, and

B. using said structure to protect personnel and/or equipment from said effects of explosion.

11. The method of claim wherein said means pressurizing the space between said first and second liner means is pressurized to a pressure between about 5 and about 3,000 pounds per square inch.

12. The structure of claim 1 further including 5 a soft envelope, containing pressurized fluid, and formed at least partially of flexible resilient resilient material, said soft envelope generally overlaying the exterior of said 15. The structure of claim 14 wherein said hard envelope is pressurized to a pressure between 100 and about 3,000 pounds per square inch, and said soft envelope is pressurized to a pressure between about 5 and less than l00 pounds per square inch. 16. A A method of using a structure to protect against the effects of an explosion having a shock wave pressure, said structure being comprised of:

space which is pressurized between said inner and outer a first high strength, relatively rigid, material liner means for liner, said space constituting l0 partially carrying out said protecting and being formed a hard envelope containing pressurized fluid, said hard engenerally of a protective shap velo e bein re u i ed to a pressure i ifi tl hi h a second flexible resilient liner means for partially carrying than th re u e of id oft enve]ope out said protecting and being formed generally of a pro- 13, Th tru t e of l im 12 h i tective shape having at least a portion thereof disposed said hard envelope is pressurized to a pressure between 100 15 Spaced from Said first line! means,

and about 3,000 pounds per square inch, and means pressurizing the space between said first and second said soft envelope is pressurized to a pressure between liner means to a Pressure between about 5 and flboul about 5 and less than 100 pounds per square inch. 3,090 Pounds P Square mch, to thereby form P 14. The structure of claim 6 further including surized envelope: a soft envelope, containing pressurized fluid, and formed at Sald method q p s s the P of: D

least partially of flexible resilient material, said soft enassPmblymg said structure a desired 01161113110" and velope generally overlaying the exterior of said space enflmnn'lemi and which is pressurized between said first and second liner 531d sifuctm'e to P Personnel and/Or q 'P means, Said space constituting men t from said effects of explosion.

17. The method of claim 16 wherein 581d space IS presa hard envelope containing pressurized fluid, said hard en velope being pressurized to a pressure significantly higher than the pressure of said soft envelope.

surized to between and 3,000 pounds per square inch. 

1. A shelter for protecting personnel and/or equipment from the effects of an explosion having a shock wave pressure comprising: a metal dome-like inner liner formed generally hemispherical in shape and having its edges sealed to a surface, a flexible dome-like outer liner formed generally hemispherical in shape having at least a portion thereof disposed spaced from said metal inner liner and having its edges sealed to the surface, and means pressurizing the space between said inner and outer liner to a pressure at least as great as the shock wave pressure.
 2. The shelter of claim 1 further including a door for gaining access to the interior of the shelter having an interior metal liner and an outer structure formed of an outer flexible wall, an inner flexible wall spaced from said outer wall and disposed adjacent said interior metal liner, flexible web means interconnecting said inner and outer flexible walls forming cavities for compartmentalizing said space, and compressible fluid means pressurizing said cavities to a pressure at least as great as said shock wave pressure.
 3. A structure, for protecting personnel and/or equipment from the effects of explosion having a shock wave pressure, comprising: a metal inner liner means for partially carrying out said protecting and being formed generally of a protective shape and having its edges sealed to a surface, a flexible outer liner means for partially carrying out said protecting and being formed generally of a protective shape having at least a portion thereof disposed spaced from said metal inner liner means and said outer liner means having its edges sealed to a surface, and means pressurizing the space between said inner and outer liner means to a pressure at least as great as the shock wave pressure.
 4. A shelter for protecting personnel and/or equipment from the effects of an explosion having a shock wave pressure comprising: a metal dome-like inner liner formed generally hemispherical in shape and having its edges sealed to a surface, a flexible dome-like outer liner formed generally hemispherical in shape having at least a portion thereof disposed spaced from said metal inner liner and having its edges sealed to the surface, and means pressurizing the space between said inner and outer liner to a pressure between about 5 and about 3,000 pounds per square inch.
 5. A structure as in claim 3 wherein said means pressurizing the space between said inner and outer liner means is pressurized to a pressure between about 5 and about 3,000 pounds per square inch.
 6. A structure for protecting personnel and/or equipment from the effects of an explosion having a shock wave pressure comprising: a first high strength, relatively rigid, material liner means for partially carrying out said protecting and being formed generally of a protective shape and having its general extremities sealed to a surface, a second flexible resilient liner means for partially carrying out said protecting and being formed generally of a protective shape having at least a portion thereof disposed spaced from said first liner means and said second liner means having its general extremities sealed to a surface, and means pressurizing the space between said first and second liner means to a pressure at least as great as the shock wave pressure.
 7. A structure as in claim 6 wherein said means pressurizing the space between said first and second liner means is pressurized to a pressure between about 5 and about 3,000 pounds per square inch.
 8. The structure of claim 1 further including a door for gaining access to the interior of the shelter having an interior metal liner and an outer structure formed of an outer flexible wall, an inner flexible wall spaced from said outer wall and disposed adjacent said interior metal liner, flexible web means interconnecting said inner and outer flexible walls forming cavities for compartmentalizing said space, and compressible fluid means pressurizing said cavities to a pressure at least as great as said shock wave pressure.
 9. A method of using a structure to protect against the effects of a nuclear explosion having a shock wave pressure, said structure being comprised of: a metal dome-like inner liner formed generally hemispherical in shape and having its edges sealed to a surface, a flexible dome-like outer liner formed generally hemispherical in shape having at least a portion thereof disposed spaced from said metal inner liner and havings its edges sealed to the surface, and means pressurizing the space between said inner and outer liner to a pressure at least as great as the shock wave pressure, said method comprising the steps of: A. assemblying said structure in a desired orientation and environment, and B. using said structure to protect personnel and/or equipment from said effects of explosion.
 10. A method of using a structure to protect against the effects of a nuclear explosion having a shock wave pressure, said structure being comprised of: a first high strength, relatively rigid, material liner means for partially carrying out said protecting and being formed generally of a protective shape and having its general extremities sealed to a surface, a second flexible resilient liner means for partially carrying out said protecting and being formed generally of a protective shape having at least a portion thereof disposed spaced from said first liner means and said second liner means having its general extremities sealed to a surface, and means pressurizing the space between said first and second liner means to a pressure at least as great as the shock wave pressure, said method comprising the steps of: A. assembling said structure in a desired orientation and environment, and B. using said structure to protect personnel and/or equipment from said effects of explosion.
 11. The method of claim 10 wherein said means pressurizing the space between said first and second liner means is pressurized to a pressure between about 5 and about 3,000 pounds per square inch.
 12. The structure of claim 1 further including a soft envelope, containing pressurized fluid, and formed at least partially of flexible resilient resilient material, said soft envelope generally overlaying the exterior of said space which is pressurized between said inner and outer liner, said space constituting a hard envelope containing pressurized fluid, said hard envelope being pressurized to a pressure significantly higher than the pressure of said soft envelope.
 13. The structure of claim 12 wherein said hard envelope is pressurized to a pressure between 100 and about 3,000 pounds per square inch, and said soft envelope is pressurized to a pressure between about 5 and less than 100 pounds per square inch.
 14. The structure of claim 6 further including a soft envelope, containing pressurized fluid, and formed at least partially of flexible resilient material, said soft envelope generally overlaying the exterior of said space which is pressurized between said first and second liner means, said space constituting a hard envelope containing pressurized fluid, said hard envelope being pressurized to a pressure significantly higher than the pressure of said soft envelope.
 15. The structure of claim 14 wherein said hard envelope is pressurized to a pressure between 100 and about 3,000 pounds per square inch, and said soft envelope is pressurized to a prEssure between about 5 and less than 100 pounds per square inch.
 16. A A method of using a structure to protect against the effects of an explosion having a shock wave pressure, said structure being comprised of: a first high strength, relatively rigid, material liner means for partially carrying out said protecting and being formed generally of a protective shape, a second flexible resilient liner means for partially carrying out said protecting and being formed generally of a protective shape having at least a portion thereof disposed spaced from said first liner means, means pressurizing the space between said first and second liner means to a pressure between about 5 and about 3,000 pounds per square inch, to thereby form a pressurized envelope, said method comprising the steps of: A. assemblying said structure in a desired orientation and environment, and B. using said structure to protect personnel and/or equipment from said effects of explosion.
 17. The method of claim 16 wherein said space is pressurized to between 100 and 3,000 pounds per square inch. 